Centrifugal fan



June 19, 1951 s PUNT ,557,201

. CENTRIFUGAL FAN Filed July 26, 1948 2 Sheets-Sheet l ATTonNEYs June 19, 1951 s. PUNT 2,557,201

CENTRIFUGAL FAN Filed July 26, 1948 2 Sheets-Sheet 2 Y W6 l. y m w HW" ,s

g m HHHHHW' NVENTOR SaMoN pum' AWTORNEYS Patented June 19, 1951 CENTRIFUGAL FAN Simon Punt, Grand Rapids, Mich.

Application July 26, 1948, Serial No. 40,678

Claims.

This invention relates to a centrifugal fan for forcing air under pressure and which may be .used particularly with pipe organs, though not limited solely in use thereto. It is an object and purpose of the present invention to eliminate noise .and vibration, increase eiiciency, and in particular provide a centrifugal fan structure which is economical to manufacture and assemble, parts being readily fabricated and secured together to provide Va fan rotor of an -especially sturdy and durable character.

An understanding of vthe invention may be had from the following description, taken in connection with the accompanying drawings, in which,

Fig. l is a vertical section through a centrifugal ian and a housing therefor, the plane of the .section through the fan being substantially that indicated 4by the line I-I of Fig. 2, Y

Fig. 2 is a longitudinal section through the ian rotor substantially on the plane of line 2-.2 of Fig. 1, and

Fig. 3 is an enlarged fragmentary perspective view of the parts used in the fan rotor construction.

Like reference characters 4refer to like parts in the different gures of the drawings, and the sections are taken looking in the directions indicated by the arrows associated with the section lines.

In the `construction of the fan rotor, a central or intermediate ring I has a plurality of radial spokes 2 joining at their inner ends with a central disk 3 which preferably is stamped or .cut from flat plate material, which material may be of a non-metallic character, for example, relatively strong paperboard ber stock, Masonite or the like. The ring I from its outer edge, in alignment with each of the spokes 2, has a radial slot 4 extending part of the length of each spoke 2; and between the spokes a plurality of spaced radial slots 5 are cut from the inner edge of the ring part way through it towards its outer edge or periphery.

Associated with the central or intermediate member are two additional members made of the same material. One comprises a ring 6, which is shown as having a relatively large central opening 1 therein. In practice the width of the ring 6 is somewhat greater than the width of the ring I, their exterior diameters being the same. The ring 6 from its outer edge radially inward is provided with a plurality of spaced slots 8 which extend partly through the ring from its outer edge toward its inner opening 1.

The other side member 9, having likewise the same exterior diameter as the others, has a small central opening I0 therein so that such member is substantially a solid disk except for its relatively small central opening, and for a plurality of radial slots II spaced around its outer edge and extending inwardly therefrom substantially the same distances as the slots 8 in the ring 6. In the assembly of the rotor the three members, the intermediate or middle ring I and the two side members S and 9, are held in parallel spaced relation by cross vanes. In association with each .of the slots 4 a generally rectangular vane I2 is provided which, midway between its ends, has grooves E3, one at each side, extending parallel to the ends of the vane I2 and of a length such that the adjacent edges of the ring I and spokes 2 at the slots 4 are slidably received in the grooves. At the lower outer corner, as shown in Fig. 3, a tongue I4 projects downward, being of a reduced width and of a length to t in a slot II. At its upper outer corner each of the vanes I2 has a similar tongue I5 extending upwardly, having the proper dimensional width and length to lit in a radial slot 8. At the inner upper corner of the vane I2 a second upwardly extending tongue I6 is provided, which is so positioned that when the vane is assembled with the three parallel parts of the rotor, such tongues I6 of the varies I2 are located in the large opening 1 of ring 6 with their outer ends against the inner edge of said ring. There are as many of the vanes I2 as there are spokes 2 in conjunction with the middle ring I, four being shown in the drawings, though the number is obviously capable of variation.

The rotor is completed by a plurality of vanes I1 of flat material and rectangular in form, each at its outer edge midway between its upper and lower ends being provided with a horizontal slot I8 extending partly through a vane I1. At its upper and lower outer corner portions upwardly and downwardly narrowed tongues I9 are provided. One of these vanes I1 is associated with cach of the slots 5, the slot I8 overlapping the ring l from the bottom of the slot 5 to its outer edge, and the slot 5 receiving the narrowed portion of the vane I1 inwardly from the bottom of the slot I8. The tongues I9 and 25, respectively, are located in the slots 8 and I I. It is to be understood that this description of the structure is with reference to Fig. 3, in which the vanos are shown vertically positioned and the ring members I, 6 and 9 as in horizontal position, though in actual use of the rotor, the ring members may be located in parallel Vertical planes and the several vanos be radially disposed in spaced relation to each other, as in Fig. 1. The vanes where they are in connection with the spaced members I, 6 and 9 are permanently secured thereto in a secure xed relation of the parts to each other.

The central disk 3 at the inner ends of the spokes 2 has an axial opening therethrough (Fig. 2). A coupling socket 2| is provided with a reduced diameter threaded stem 22 which passes through the opening in the disk 3 and also through metallic washers 23 and washers 24 of a resilient material under washers 23, the threaded stem 22 receiving a nut So that all of the parts 23, 24 and the central disk 3, are securely clamped together. The sleeve 2I has a socket to receive the shaft of a motor or other source of power for rotating the fan rotor.

The fan vrotor is adapted to be mounted for rotation within an enclosing housing 25 which, in conjunction with pipe organs, will be of a sound absorbing and insulating material, and within which is a casing receiving the rotor, indicated at 26, from which an outlet 2l leads for the expulsion of the air forced by the fan rotor. The entrance of air t the rotor is through the large opening 1 of the ring 6 at one side. The inward projection of the longer vanes I2 aids in trapping air and forcing it radially outward.

It is apparent that the vanes Il are held against moving radially outward under centrifugal force by reason of their connection at their middles to the intermediate ring I at the slots 5, which connection places the middle part of each 0f the vanes I 'I back of a solid portion of the ring I. It is further apparent that the vanes I2 are held from outward radial movement under centrifugal force by the stops interposed by the tongues I6, which at their outer edges come against the inner curved edge of the ring 6. The sound deadening or insulating character of the casing and of the resilient rubber washers at 24, also the material of the rotor insure against reproduction and possible amplifying of undesired sounds coming from the fan to be conducted to and transmitted from the organ. The structure is economical, and is readily manufactured and assembled. It is of light weight and of a sturdy and durable character.

The invention is defined in the appended claims and is to be considered comprehensive of all forms of structure coming within their scope.

I claim:

1. In a structure as described, an intermediate ring having a circular periphery and spokes extending inwardly from the ring and meeting at a common center, said ring and each of said spokes being radially slotted through the ring and part of the length of said spokes, and said ring being further slotted from its inner edges radially outward part of the width thereof at spaced points between said spokes, said ring and spokes being of flat material, spaced side members of circular outline and of substantially the same exterior diameter as said' ring paralleling the ring and its spokes, one of said sides having a relatively large open area within its outline, vanes having guide grooves between their ends on opposite sides inserted in the radial slots through said ring and spokes and extending to said parallel sides,

other vanes slotted between their ends from their outer edges inwardly connected to said ring at said radial slots extending outwardly from the inner edges of said ring, each of said parallel side members having spaced radial slots therein in alignment with the ends of all of the vanes, each of said vanes at each end thereof and for a part of its width inwardly having a projecting tongue received in said slots of the side members and each of the vanes connected with said spokes extending radially inward greater distances than the remaining vanes, and each at each end edge thereof having stop means extending therefrom through the said mentioned relatively large opening in one of said sides.

2. A structure as defined in claim l, the other of said sides having a small central opening, and a socket member permanently secured at the inner meeting ends of said spokes and extending therethrough, having a socket extending toward said relatively small opening, through which opening a drive shaft is adapted to be passed to connect with the socket member.

3. A structure as dened in claim 1, said side f members and intermediate member and said vanes being of flat material of a fibrous nature having sound deadening properties.

4. A structure as dened in claim 1, the radial width of said ring member being less than the radial width of the side member having the large opening therethrough.

5. A centrifugal rotor comprising, two spaced apart circular sides of equal diameter, one having a relatively large central opening therethrough, and an intermediate circular member between said sides and of the same diameter thereof having an outer ring and an air passing central opening, radial vanes located at equally spaced distances apart connected with said side members and intermediate member and having inwardly extending edge portions extending radially inward beyond the edges of said large opening in one of said side members and the central opening of the intermediate member, slots in said side members, said vanes having portions received in said slots, stops at the inner portions of said radial vanes bearing against the edges of said large opening of the one of said side members, and intermediate spaced apart vanes between the rst mentioned radial vanes spaced equally from each other and said rst mentioned radial vanes connected with said parallel sides and intermediate member and permanently secured thereto, said last mentioned vanes and the intermediate member having interlocking connections preventing radial movement thereof With respect to said sides and intermediate parallel member.

SIMON PUNT.

REFERENCES CITED UNITED STATES PATENTS Name Date Nygren May 4, 1948 Number 

